I read up on the previous threads on this for this generation 4R and in most cases it ended up with most people saying or finding out they had a loosened/broken bolt and/or busted pulley where it separated at the rubber connections. In every case I've not really seen what they considered wobble that was severe enough to be concerned about and/or how bad the wobble was. It's a 2000 SR5 5VZ with 275k miles on it.
I just did the most recent timing belt/water pump a couple hundred miles ago; this is the 3rd time I've done this job on this type of engine, 2nd time I've done it on this particular 4Runner, last time was at 185k with no issues) and was crawling under it to fix a rattle while engine running and noticed the pulley section itself (not the main section) seemed just slightly wobbly but not throwing the belt around really. Just enough to never remember it being like that honestly but not enough to definitively say something's not right as I rarely have to crawl under it and be directly under the crank while running.
Now I'm questioning if something is wrong. I would've thought the same thing as others in that my bolt came loose but the key and keyway looked perfectly fine when I removed the pulley for the timing belt job and slid back on perfectly fine. I torqued the same bolt to 217 ft-lbs without issue with a cal'd torque wrench just as last time; it's the larger version that calls for the higher of the two torques. Would approximately 1/8" of runout on the front of the pulley face be cause for concern? I.e. if I put a tape measure to the front of the pulley face and extended it towards the front of the car my best estimate is about 1/8" difference at worst. Now that i watch the video I guess it just looks like a lot more wobble from underneath when it's 12" from my face than from up top.
My father in law mainly drives this locally now so not really too worried about being stranded but wondering how many people have an actual slight wobble but just never noticed it until things started banging around/running rough.
Video:
https://streamable.com/9haakk